It sounds to me like a character set problem between PHP, the galley, and the DBMS. First, try making sure you're using the connection_charset and database_charset options in your config.inc.php file. You might also be able to patch in some work-arounds for problems like this that have not yet been released; see http://pkp.sfu.ca/bugzilla/show_bug.cgi?id=2324
Also make sure that you're saving your HTML documents using the UTF-8 encoding.
There are several patches you'll need to apply to get this change in place:
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